The word "train" is actually a reference to a series of connected "whatever" following one another.
IE a train of thoughts, a camel train (where one camel is tethered to the behind of the one in front) and of course the far more commonly used train of railway cars.
Hence the word train is - through common use - a contraction of railway train. "Railway" being scope/domain of the train in question. IE the train of cars is intended to only ever run on rails.
So riffing off "railway train" for a vehicle that is limited to land but not rails ... land train. A train of cars that intends to be capable of going anywhere on land.
Plane is a contraction of aeroplane - aero referring to air. Clearly, aeroplane is intended to be limited in scope/domain by air. So saying "sky aeroplane" is similar to saying "ATM machine" - somewhat silly. But saying "land train" is an exact reference to the machine and what it's intended scope/domain is.
Now.. what is a sea plane? Strictly, a "plane"(no aero) limited in scope/domain by "sea" IE a submarine.
But no... what we have is a contraction of "sea-landing limited aeroplane". Again, sea refers to scope/domain but only of a portion of the capability of the vehicle.
The contortions that language goes to for improved information density can lead to ambiguity instead.
Usually indeed. Besides accidental derailments, there was a time in the late 90s when a town in Canada intentionally derailed a diesel-electric locomotive and drove it down the street half a mile under its own power so they could use it as an emergency generator. The road needed to be repaired, but apparently the locomotive was fine and eventually returned to regular service.
Etymology 1
From Middle English trayne (“train”), from Old French train (“a delay, a drawing out”), from traïner (“to pull out, to draw”), from Vulgar Latin traginō, from tragō, from Latin trahō (“to pull, to draw”), ultimately from Proto-Indo-European *tregʰ- (“to pull, draw, drag”). The verb was derived from the noun in Middle English. (https://en.wiktionary.org/wiki/train)
A group of people following an important figure such as a king or noble; a retinue, a group of retainers. [from 14th c.]
A group of animals, vehicles, or people that follow one another in a line, such as a wagon train; a caravan or procession. [from 15th c.]
The men and vehicles following an army, which carry artillery and other equipment for battle or siege. [from 16th c.]
IE a train of thoughts, a camel train (where one camel is tethered to the behind of the one in front) and of course the far more commonly used train of railway cars.
Hence the word train is - through common use - a contraction of railway train. "Railway" being scope/domain of the train in question. IE the train of cars is intended to only ever run on rails.
So riffing off "railway train" for a vehicle that is limited to land but not rails ... land train. A train of cars that intends to be capable of going anywhere on land.
Plane is a contraction of aeroplane - aero referring to air. Clearly, aeroplane is intended to be limited in scope/domain by air. So saying "sky aeroplane" is similar to saying "ATM machine" - somewhat silly. But saying "land train" is an exact reference to the machine and what it's intended scope/domain is.
Now.. what is a sea plane? Strictly, a "plane"(no aero) limited in scope/domain by "sea" IE a submarine.
But no... what we have is a contraction of "sea-landing limited aeroplane". Again, sea refers to scope/domain but only of a portion of the capability of the vehicle.
The contortions that language goes to for improved information density can lead to ambiguity instead.
EDIT: trying to remove ambiguity myself!